Automatic spark adjuster



June 2, 1936. H. .1. DE N. M COLLUM 2042616- AUTOMATIC SPARK ADJUSTEROriginal F'iied Feb. 24, 1953 INVENTOR Henry J.eM Mc'6'oll um ATTORNEYPatented June 2, 1936 UNH'E STATES PATENT OFFIE Application February 24,1933, Serial N0. 658,381 .Renewed. October 31, 1935 8 Claims.

'This invention relates 110 the automatic re-v tardation of the ignitionspark Torinterna1 combustion cengines installed on road vehicles 01' m0-1:0r cars of any description, and has for its 0bject the temporaryproduction of such retardation whenever the vehicle is started. intomotion from a condition of rast, 01' :has its existing rate of motionsubstantially accelera;ted 01 is being driven up a, grade, under all nfwhich conditions substantial reta;rdation of the moment of ignition 0Teach .cylincler charge '0f fuel beyond tha.t at Whic'h the best resultsare Obtained. When running at uniform speed er under lighter loads, isdesirable for smooth and. efficient operation of the engine, und for theavoidance of internal strains and overheating. The spar-k is alsoretarded when the engine is idling.

The best .form of apparatus embodying my invention, e 1t present kno-wn130 me, anal sundry modifications thereof, are illustrated in -theaccompanying sheet of drawings, in which,

Fig. 1 is a plan view '0f a portion of an interna;l combustionenginerand the circuit breaker for the ignition system there0f, with myinvention applied thereto, cer.tain parbs being broken away and othersshown in section.

F'ig. 2 is a similar side elevatian, 0n a smaller scale.

Fig. 3 isa view of a modification,

Fig. 4, is a detail of another modification, 'and Fig. 5 shows theinvention applied to another form o'f ignitiom device.

Throughout the drawing like r.eference characters indicate 'like parts.

In all =the figures 0f the drawing, the numeral l indicates the cylinderblock of a standard for-m of motor for automobile construction, then-umeral 2 is the intake manifold, andthe numeral 3 is Ehe carburetortherefo-r. 'Ihe carburetor 3 has the usual throttle valve sha;ft 4,carrying stop arm 5, yieldingly forced towa;rd stop 5m, so placed. as tohold throttle valve in idling p0sici0n, loy tension spring 6, anchoreda't 1, andmanuall5 controllecl by a lost-motion linkage 48 extending 130accelerator pedal 9, normal'ly retracted b-y expansion spring 10confined betWeen it a nd the footboard. H.

A standard form of ro'tary circuit breaker o1 spark timer for the=ignition system having the cylindricl casing 29 is shown in Figs. 1 1103 0f the drawing. In the interior of said casing are pivoted at 23, 23,two circui't breaker arms 23, 24, carrying bear'ing lugs 28, 28,cooperating with multiple cam 21 secured 130 a shaft 22 geared torotatewith the engine crank-sha'ft. These breaker (C1. ISO-77') arms 24,2G, are electrically co'nnecoed. m the bindlng post 26, while the fixed.contacts 21., 21, with which they cooperate, are grounded. The springs25, 2'5, normally hold the 2irms 24 against contaccs 2'l' until the cam2| momentarilyseparates the points one after the other and breaks thecircuit, thereby producing the spark for ignition of each cylinclercharge. 'Ihe casing 29 is loosely journaled on cam-shaft 22, whichrotates in a clockwise direction as indicated -loy the arrow in Fig. 1.The casing and circuit breaker arms 22 carried therein are preventedfrom ro-ta;ting by rod !9 pivc-tesl at one end to the external CasingIng, o1 lever arm 2B, and ab ehe ooher end anchored in any desired wayin a position which Will properly time the moment of each breaking ofthe circuit ancl consequent spark production. If the lug ismovedslight'ly in a clockwise direction, looking a1; Figs. 1 and. 2, sothat the diametr'ical line I1I.17 is .moved to position x -ac the spar.kwill be retared 110 that angular extent:

In p-ractically all modernmotor cars the spark timing is automaticallycontrolled by a cen trifu'- gal or other governing mechanism geamed. tothe engine, so that the spark is automatically ad.- vanced by rotatingcam in a clockWise direction With respect so its axis more 01 less asthe speed of revolution of the ehg1'ne crank-shaft increases. Underusual conditlons of operation the standard 4-cycle gas engine performsmost efficiently with an ad.vance of the: ignition spark a number ofdegrees beyond the crank dea.d center. When starting, sharp'lyaccelerating 01' lugging, (i. e. laboring ab very 10W sp'eed on highgear) with a heavy 1oad 0 :1 the engine, however, ehe spark must besomewhat less advanced. These conflicting requirements, which sometimesarise at the same engine speed, have made it impmcticalole 1:0 sei; thecentrifugal governing mechanisms so aus 130 p-roduce ab theirminimumoperating speed the amount o1 spark advance best suited for the firstdass of conditions, such as the moderate running a1: a moderate speeda.long a level road with a lightly loaded. cm, because When the car isheavily loaded, or is going upgrade, or both, anal is running at thesame speed, the spark should. be much less advanced. Consequently, thestandard apparatus governed .by engine speed and now used 1:0automatica-lly ad.- just, or time, the ignition spark are all set coproduce a predetermined minimum spark advance which is too slight top=r0duce highest efficiency under ordinary conclitions of running 011 a.smooth, level road, anti this has to be done 130 avoid an excess sparkadvance when starting, accelerating or lugging.

My invention, hereinafter to be described more in detail, can be usedWith, and a-s supplementary to, the said standard automatic speedactuated spark control, in that it automatically retards the spark whenthe car is started, accelerated, or driven uphill and that this is doneindependently of any contemporaneous speed responsive adjusted governorcontrol.

With approximately uniform load conditions,

the spark should (generally speaking) be advanced proportionately to theengine speed, as every motorist knows, and the centrifugal gevernorfulfills this requirement, but has tobe set for level road conditionsand does not compensate for any considerable increase in load at a givenspeed, such as occurs when a car is being driven up a. steep grade. Whenclimbing a hil1 ehe throttle is opened wider, more combustible mixtureis drawn into the cylinders for each cycle o1 operation, such largerCharge is more quickly und sharply compressed, and. the spark should becorrespondingly retarded to prevent knocking, over-heating and strainingof the motor, but I;he centrifugal, engine-driven spark controlleralways maintains the same spark advance for the same speed no matterwhat the load and throttle conditions. Also when the load on the engineis suddenly increased by throwing in the clutch on starting or shiftingto a higher gear, the spark should be retarded sharply, but if thecantrifugal apparatus alone is in use, this retardation will not occurbecause it has been set to produce the greater angle of advance suitablefor other conditions.

I have discovered that both o-f these difiiculties can be o-vercome ifthe extreme retardation of the spark so desirable under ehe aboverecited special conditions is automatically eifected by a deviceactuated by the combined influences of gravity and inertia, the simplestform of which is a smal1 pendulum connected to the'adjusting lug, or1ever arm 26, of Ishe circuit breaker or ignition timer.

Referring to Figs. 1 anti 2, a pendulum weight I3 is there shown assuspended by rod I4 from shaft I2 journaled in the ears I6, I6, of thebracket I5, fastened to the top of the cylinder block I by screws 45,45. Cross pins I'I, I'I, prevent shaft I2 from sliding endwise. Thenumeral I8 designates a. cra.nk arm projecting upward from shaft I2, andto which one end. of rod I9 is pivoted. The numerals 36 and 60 designatepins limiting the oscillations of pendulum rod I4.

This embocliment of my invention, shown in Figs. 1 and 2, operates asfollows: Assuming that the car moves from right to left (as indicated bythe arrow between Figs. 1 and 2) when running forward, the inertia ofthe pendulum weight I3 will cause it to lag behind when the car isstarted, or has its motion sharply accelerated; thus swinging the partsI 3, I 4, I8, I9, 26 into the broken line positions shown, and retardingthe spark to the desired extent, until gravity has had time to pul1 thependulum back to its normal position shown in fu1l lines. Similar1y,when the car is going upgrade, the pendulum swings toward the brokenline position and stays there, thus retarding the spark more or less solong as the car is on an upgrade. As the spark must not be ret ardedbeyond the point corresponding to crank dead center, a stop, such as pin60, must be provided to engage the train o1 mechanism at some point,either at the pendulum or at the timer, or at some intermediate point,to prevent; any such excess retardation. Also, as it; might not beadvisable to have the spark abnormally advanced while going down hi1l,and certainly not when starting backvvards With the car, a second stopmeans, such as Ishe pin 36, should be installed to prevent the pendulumswinging too far to the left of its normal vertical position, shown infull lines. It is assumed, o1 course, that the usual centrifugallyactuated timing device (not shown) operates an the cam 2I, or cam shaft22, and that no manua11y operated control device for timing the spark isprovided, the latter usually being omitted from modern pleasure carequipment.

In the arrangement shown in Fig. 3, the car is supposed to travel fromleft to right (as indicated by the arrow) When running forward, and aninertia device o1 the electro-magnetic type, (the details of which werenot invented by me) is shown as another specific embodiment of theunderlying principle of my generic invention. The body cf mercury 33 inthe horizontally extending glass taube 32, supported 0n bracket 35,there serves as the inertia controlled element, taking I:he place of thependulum hob I3 shown in Figs. 1 and 2. When the power clutch of the carengages and starts the car moving to the right, the mercury surges backto the left, anal bridges contacts 34, 36, thus completing circuit 3Ithrough battery 38 ahd solenoid 31. The magnetic attraction then pullscore 39 into solenoid 3'I, expanding spring 4I, to which ehe core isconnected by link 40. The lug, or lever arm 26, 01" the timer 29 isconnected to this linkage ab any convenient point, and the spark isretarded accordingly. When the car is running at a. uniform speed on alevel road I:he mercury 33 does not touch the contact, or shortelectrode '34, solenoid 31 is de-energized. and. spring ..4I pul1s thetimer into its normally advanced. position. When the car runs up a steephill, short electrode 34 is again immersed in the mercury and the sparkis retarded as is desired.

Obviously, a, sliding weight, such as 53 (shown in Fig. 4), ha.ving ananti-friction mounting 54 on a, horizontal track 52, supported by abracket 55 on any portion of the motor car, is the mechanical equivalentof the pendulum apparatus I3, I4, I2, shown in Figs. 1 and 2, for allpurposes of this invention. Compression spring 56 would perform thefunction of keeping the weight in one position so long as the car isrunning ab a. uniform speed along a1evel road, just the same as gravityholds the bendulum I3, I4, in one position under similar conditions.starts, or accelerates, the inertia .of weight 53 would cause it to lagmomentarily, thus compressing spring 56 and moving to the right alongtrack 52. Thereupon, link II9, which should be connected to weight 53a1: 51 and to 1ug I 20 on timer 23 (if this sliding weight weresubstituted for a swinging pendulum) would rotate the time r casing inthe desired clockwise direction and automatically retard the sparkmomentarily as before.

When the lag caused by the weight inertia, has been overcome by spring56 and the weight moved Also, when I;he car back to normal position(further acceleration of the car motion having ceased) the spark timingwill return to normal. Also, whenever the car is driven uphill Weight 53will tend to slide backward, compressing spring 56 more or less andcorrespondingly retarding the spark.

My inventi0n has been hereinabove described as applied to the older formof timer and dis- 75 tributor in which the entire casing 29 is rotatedin one direction or the other to varythe degree of spark advance, lautin such c onstruction Izhe numerous wires (n0t shown) leading to thespark plugs and to the coil must be fiexed with every adjustingmovement, thus requiring the pendu- 1um to do a considerable amount cfwork. In Fig. 5, however, I have shown itas applled to a more modernform of spark adjusting and distributing apparatus in which the casingI29 is stationary, and on1y an internal plate (not shown) which carriesthe circuit breaker arms 24, 24, and cooperating contacts 2'I 2'I,rotates back ancl forth aber; shaft 22, being controlled for thispurpose by lever arm 220 which projects radially from it through a s1ot22I in the casing. The spark plug wires GI, GI, and the wire 62 so thecoi1 then pass through the stationary cap 63 of casing I29 to thestationary contacts (not shown) of the stationary distributor head. Thependulum II3 of my invention can then be suspended from a pivot I I2 onthe exterior of casing I29, ancl the pendulum rod. I I4 is provided witha s1ot I I8 through which the lever arm 228 projects. The pendulum thenhas 130 clo only the"work of rotating back anti forth the said lightplate, which carries the circuit breaker arms and the coaperatingcontacts, and the apparatus is much more sensitive, thus permitting theuse of a mueh lighter pendulum weight. Also, its operation is maintaineduniform ab all times, being unaflected by variations in stiffness of the1ead wires, such as might develop with age, or from readjustment of thewires such as might result from rewiring of the ignition system, etc.

II: will thus be seen that When my invention, in whatever form it isembodied, iscombinecl with the centrifuga], or other speed actuated,form 0f automatic spark adjuster, the resultant timing of the spark is ajoint function of the two devices. If the engine is unloaded and runningslow1y enough 120 cause the centrifugal apparatus to retard the spark tothe minimum of which it is capable, and the clutch is thrown in, thependu- 111m Will temporarily further retard the spark. If the car isrunning ab a speed such that the spark has been advanced a given numberof degrees, and is suddenly accelerated, the pendulum will alsomomentarily further retard 117 to a greater or less extent according tothe sharpness of the acceleration, and will thereafter graduallysurrender all control of the timing to the centrifugal apparatus. If nocentrifugal apparatus were employed, but the spark timing were manuallyeffected, my invention would still automatically retard the spark duringthe desired periods above defined.

Various other changes cou1d be made in the details of construction hereillustrated and described, and equally without departing from theunderlying novel principle of my invention; which involves the use insome way of the inertia or weight of an element loosely mounted withreference to the running gear of a motor car, to automatioally retardthe time of the ignition of the charge whenever the said element issuddenly put into motion, or accelerated in motion, or tl'1e car isdriven onto an upgrade.

An additional automatic spark control which may be used in combinationwith my above described. invention, or independently thereof, is alsoillustrated in Figs. 2 and l. Referring to Fig. 1 another lug I20 isshown projecting from the other side of casing 29 and carrying a pin I49projecting up through a s1ot 44 in a link 42,

which i s pivoteglab 43 I2o the accelerator linkage 8... The parts areso proportioned that after the retraction of the accelerator pedal 9 hasallowed the t:hr0ttle valve to assurne idling position and the lostmotion connection 48 in linkage 8 begins to open, the leih-band end ofthe s1ot 44 in link 42 will engage the pin I49, and the final movementof the aocelerator pedal 1:0 its position of rast will retard. the sparkso zero position. This permits slow anti smooth idling and cons -zquentreconomy of fue1. The abovedescribed serles o1" operations would alsooccur whenever the modifieol inertia element of Fig. 4 should beemployed, wlth its rod. II9 conneeted to lug I20, as previouslyclescribed. When the accelerator peda1 is pressed down 110 open ehethrottle valve and the clutch has become sufficiently engaged toaccelerate the motion of the car, the spring 56, or pendulum weight I3,first advanoes the spark to the normal position for which thecentrifugalgoverning device is Set, and thereafter the manipulation of theacoelerator has no effect on tl1e timing (because of the length of slot44) unt'1l the parts again return to idling position. While theaccelerator pedal is pressed' down to any extent suflicient to open thethrott1e valve beyond its idling p0sit-ion, pin I49 may then move freelyin s1ot 44 without comi-ng in contact with either end thereof, so thatthe spark timing is thensolely under control of pendulurn I3 erslidingweight 53, which ever has been installed, together with the usualcentrifugal governor.

Of course, in the modification shown in Fig. 4 the effeotive pull ofspring I EI on lug. I2@ musi;

slightly exceecl the pull of the spring 55 in the oppositedireotion inOrder 110 have the sparl: recarciation thus prod.uced by the pedal.'When be car is started, or accelerated, or running uphill, however, theaecelerator pedal 9 will always be dep-ressed, so that the lost motionconnection 44-I49 will release lug I20, and spring 56 and weight 53 willthen have so1e control of the timer member 29, allowing the inertia orthe gravitation of the weight 53 to properly retard. the spark duringthe starting and accelerating periods, or when hill climbing, in thedesired manner before described.

Other means actuated by the pendulum, or equivalent inertia-controlledelement, and. operative to retard the spark, might be substituted forthe purely mechanical devices herein shown which mecham'cally s.hift thepoint in eaoh cycle of engine operation at which the circuit producingthe spark is closed or opened, as the case may be.

Having described. my invention, I claim:

1. In a spark timing apparatus for a gas propelled motor car havingadjustable ro'oary cirouit breakers normally sei; I;o produce the sparkigniting the oylinder-charge somewhat in advance of the dead. centerposition of the crank cf the engine propelling said car, the combinationof mechanism comprising an element of substantlal weight so mounted. onsaid. car as to be movable longitudinally thereof, with means actuatedby said we-ight element operative to retard the spark whenever saidweight element moves toward the rear of the said car; whereby, wheneverthe said car is started forward or has its motion in tha1; directionsubstantially accelerated, tne temporary lag in motion of said weightelement will contemporaneously retard the spark.

2. A combination such as defined in claim 1 in which said weight elementis a pendulum.

3. An apparatus such as defined. in claim 1 in Which said Weight elementis slidingly mounted on a horizontal track combined with a, springnormally forcing said weight toward the fronl; of the said car.

4. An apparatus such as defined in claim 1 combined With means forpreventing said weight element from moving far enough toward the rear ofsaid car to retard the spark beyond the dea center position of the saidengine crank.

5. An apparatus such as defined in claim 1 combined. with means forpreventing said weight element from moving to any position that wouldadvance the spark beyond the predetermined normal angle.

6. In a, spark timing apparatus for use on a. motor car having athrottle controlled carburetor delivering a combustible mixture to theintake manifold of the engine for propelling said car and an adjustablerotary circuit breaker normally set to produce the spark for ignitingsaid mixture sornewhat in advance of the arrival of the crank of saidengine at dead center position, the combination, with said abovedescribed apparatus of mechanism comprising an element; yieldinglymounted 011 such car and connected. to a sparktiming member of suchcircuit breaker, yielding means normally tending'to hold said element ina position which maintains such a normal spark timing, and meansresponsive only to sudden movements and acceleration of movement's ofthe car for automatically moving said element in a direction which willretard said spark; whereby such spark retardation is ensured wheneVersaid car is started or accelerated in forward motion, or such carburetorthrottle is brought to id1ing position.

7. In a spark timing apparatus for use on a motor car having a throttlecontrolled carburetor delivering a combustible mixture t0 the intakemanifold of the engine which prope1s said car,

with a spring-retracted pedal controlling said throttle and anadjustable rotary circuit breaker having a member controlling the timingofthe spark f0r igniting said mixture normally set to produce such sparksomewhat in advance of the arrival of the crank of said engine at deadcenter position, the combination, with said above described apparatus,of a lost-motion connection from such pedal to sald spark-timing memberand mechanism comprising an element yieldingly mounted on such car andconnected 150 said sparktiming member of such circuit breaker, yieldingmeans normally tending to hold seid element in a position whichmalntains such a normal spark timing, and means responsive only 130sudclen movements and acceleration of movements of the car forautomatically moving said element in a direction which will retard saidspark; whereby such spark retardation is ensured whenever said car isstarted or accelerated in forward motion, or such carburetor th'rottleis brought to idling position.

8. In a spark timing apparatus for a motor car having an internalcombustion engine for propelling it and. an acljustable rotary circuitbreaker normally set to produce the spark igniting the cylinder chargesomewhat in advance of the deadcentre position of the crank of saidengine, the combination of mechanism comprising an element; so x'n0untedon said car as to be movable longitudinally thereof, with means actuatedby said element and operative 120 retard the spark whenever said elementmoves toward the rear of the said. car; whereby, whenever said car isstarted forward, or has its motion in that direction substantiallyaccelerated, the temporary lag in motion of said element willcontemporaneously retard the spark.

HENRY J. DE N. MCCOLLUM.

